Circuitry For Ssi/Biss; Voltage Drop In The Supply; Shielding And Cable Routing - Balluff BML-S1H1-B/S6-C-M3-A-D0-KA S284 Serie Manual De Instrucciones

BML-S1H1/2-B/S6 _ C-M3 _ A-D0-KA _ _ , _ -S284
Absolute Magnetically Coded Position Measuring System
4
Installation and connection (continued)
4.3.2

Circuitry for SSI/BISS

+Clk
–Clk
+Data
–Data
GND
U
BML...
B
Fig. 4-4: Connection example for BML... 5 V DC with controller
Clk, Data and supply are stranded in pairs (see
Fig. 4-4).
4.4

Voltage drop in the supply

The operating voltage must be 5 V ±5%. To
compensate for voltage drops in the supply, we
recommend using a regulated power supply
with sense input (Fig. 4-5).
If this is not possible or desired, integrate the
sense lines parallel to +5 V and GND lines
(Fig. 4-6).
Fig. 4-5: Power supply with sense line
Fig. 4-6: Power supply without sense line
Calculated voltage drop for BML sensor heads, with
120 Ohm input resistance per control channel according to
Fig. 4-5:
Cable length Voltage drop in BCC cable
5 m
10 m
15 m
20 m
1) See accessories
Tab. 4-3: Voltage drop (BML-S1H1/2...)
12 english
3
4
6
5
120Ω
7
8
Controller
12
8
7
11
12
8
7
11
1)
≈ 0.1 V
≈ 0.2 V
≈ 0.3 V
≈ 0.4 V
4.5

Shielding and cable routing

Defined ground!
The position measuring system and the control
cabinet must be at the same ground potential.
Shielding
To ensure electromagnetic compatibility (EMC), observe
the following:
– The cable shield must be grounded on the controller
side, i.e. connected to the protective earth conductor.
– When ducting the cable between the sensor, controller,
and power supply, it is important to avoid going near
high voltage cables due to interferences.
Stray noise from AC harmonics (e.g. from phase angle
controls or frequency converters) are especially critical
and the cable shield offers very little protection against
this.
Magnetic fields
The position measuring system is a magnetically coded
system. It is important to maintain adequate distance
between the position measuring system and strong,
external magnetic fields.
Cable routing
Do not route the cable between the position measuring
system, controller, and power supply near high voltage
cables (inductive stray noise is possible).
The cable must be routed tension-free.
Bending radius for fixed cable
The bending radius for a fixed cable must be at least 7.5
times the cable diameter.
Cable length
Max. cable length 20 m. Longer cables may be used if
their construction, shielding and routing prevent noise
interference.